I am trying to keep flathead minnows alive in a 250 gallon tank to use as feedstock for Crappies until the crappie get to a size I want to release to a pond. I have a 1000 gal aerator, UV clarifier, two five gallon buckets for filtering charcoal, lava rock, bacteria balls, fiber filters, nitrate filter, one pump for filters and one pump just for water circulation and water temp kept between 50 - 60 degrees with chiller. I have added fatheads five times (2 pounds each time) I jut added 2 pounds Saturday and today about 70 fatheads were dead. What am I doing wrong? I have six crappie about 13 inches long that live in the tank, four 11 inch bluegill and two 9 inch bullheads and wild minnows caught from the creek do very well so fish can live in the tank. Everything but fatheads.
Are you tempering the fatheads before adding
Not really. How much temp difference would cause issues? I do have a thermometer but never checked the difference.
As a somewhat general rule (5 times out of ten, it works some of the time....), the larger fish would be more subject to dissolved oxygen or water quality issues.
I wonder out of 2 lbs of fathead minnows, what percentage does 70 dead minnows equate to?
It may not be just the temperature differences, it could be water condition differences too (pH, ammonia, salinity, etc).
Sunil brings up a good point. 70 dead may be a small percentage.
And, let's face it...a trip across the countryside with 2 pounds of fish in a bag can be stressful to all the minnows and the weaker ones just don't make it.
Thanks everyone. I lost about 20 more today. They seem to have red areas on their belly. I do have a water test kit. I will check it and see. I did have some that had light spots of fungus on them, I took them out. Maybe the seller does not have good stock?
I use a 15 gallon tub with oxygen pumped in with and a high volume air pump putting air in. They are in the tub about 2 hours traveling.
Both the red spots and the 'fungus' could both be from stress.
Do you add any salts to the water during transport or in the main tank?
Also, why the bullheads in the tank?
If these are transported in a sealed bag... Temper first for 15 min then cut bag and swiftly pour contents through a net saving the minnows then put them in tank. the gases released when you open the bag can be toxic as heck when exposed to air-within a min or 2, can be lethal.
You could do a salt dip of the minnows into a 5gal solution first then net out and transfer to tank. Salt will kill the BH in the tank so don't salt that if you want the bullheads.
How often are you changing out water in tank???
This probably goes without saying...Water conditions in your holding tanks should be monitored for optimal performance.
But, the water condition of the bagged water, or in your case...the 15 gallon tub, may be just enough different than your holding tank to cause some stress. Water conditions in either may be within acceptable limits, but on the opposite ends of the range. My thoughts are that a lot of fish in a small container for extended periods will develop high ammonia levels, but not enough to kill. Once dumped into a holding tank with much lower levels of ammonia, the fish can be shocked by the difference.
It is beneficial to temperate acclimate (temper) the new fish as Snipe suggested AND gradually add some of your holding water to the new fish over the course of the acclimation time.
I have acclimated fish by placing the fish into bags or buckets 2/3 full of travel water, placing the containers in the new home for temp acclimation, and every 5 minutes add about a 1/5 the container capacity of new home water for about 20 minutes total. The only exception is if the fish start piping at the surface indicating that they are suffering for O2...adding new home water faster can help with O2, but may over-speed the temp and water condition portion of the acclimation. It can be a dance, but you get the idea.
I am not saying this IS your problem, but it helps with transfer for sure.
Since you appear to have good mechanical conditions such as aeration water circulation and multiple filtration plus UV for holding fish, I think your problem is with the source fish. During winter especially the source of your fish may have been holding the FHM for quite a while due to lower daily sales. Their holding conditions may not be as good as yours. This can be very stressful long term for retail fish sellers.
QUESTIONS - How long have these deaths been going on? Were the FHM generally okay earlier in the entire fish holding session?? Deaths just started recently?? And when did deaths start compared to when you started holding the FHM for feeding crappie?
You have no way to know how many fish the source is loosing daily. They may not be truthful. I assume you are getting the FHM always from the same place?? I suspect they are loosing the same percentage as you. Quick dying fish after you receive them and you have handled them carefully is very often due to the quality of the stocker fish which can vary a LOT - my extensive experience.
One way to check the apparent health of a new batch of FHM is put a good number in an aquarium for a short period - observe them for sores, red areas, fungus and relative healthy condition.
As mentioned, increasing the salt concentration may help reduce deaths. Look for another source or wait for their new shipment of FHM.
Odds are those minnows have been either been held in a baitfish tank, probably concrete, for several months, haven been captured during fall, or they have come from a fish farm in the south recently. Either way, they are distressed.
Fathead minnows held locally for weeks or months have likely not been fed, have been kept crowded and decline a little bit each day. At some point, they are too weak to sustain more handling and transport.
If they are coming from a fish farm in the south, they've been captured from a pond, where they likely haven't eaten much during winter months, seined, put in concrete tanks, held, then dipped, loaded onto a truck, hauled for hours, then placed into different holding tanks, then bagged up and hauled to your place.
Losing some of the minnows this time of year is to be expected. It should be skinny, weak minnows. If that's the case, expect some deaths. If they aren't skinny and weak, it could be something else.
Cody has the best idea. Set up a quarantine tank, put the minnows there for a week, and feed to your game fish as needed.
Lusk and experts - will it hurt the crappie to be fed the weak stressed fatheads that have red spots before the FHM are actually dead?? What about crappie eating FHM that will in a few days die and redspot is just getting started and not readily visible. What about predators eating sickly fish in the wild such as those having ich, aeromonas, fungus, and other health problems? Predators regularly eat weak easy to catch fish. It likely happens daily in the wild. Nature's clean up crew. What is the impact?
What about buying adding - stocking fish farm fish into ones pond where the Farm is regularly loosing some fish each night and these dead fish are discarded before customers show up?. I've seen the numbers of dead fish some fish farms toss out in the morning. The surviving fish for sale are surely infected by those fish that have died especially if infected by something other than just harsh bruising.
When I sold minnows we used to get approx. 12 dozen to a pound. So that's a gross or 144. I assume his 70 dead fish is around 1/2 pound. Just as a reference.
Those are good sized adult minnows, Flame. It's been my experience when purchasing in bulk from any given supplier, the purged FHM tend to average a bit smaller like 250-300/lb.
I'd love to load up several thousand at 144/lb.
I agree with what has been said above. I see too many unknowns to find a reason. 5 degree max water temp difference is what I try to go by, smaller fish are more fragile than larger fish.
Water temp, pH and O2 levels in the water (transport water is what I'm talking about) all need to be known. When fish haulers transport fish, they use pure O2, not air.
Like Bob said about the fish condition, I'd like to hear from the OP on the body condition of the fish - skinny or fat?
It seems the minnows are put into the main tank all at once, and not kept in a holding tank then some transferred daily for feeding. I'd rather hold the FHM in another tank and transfer daily for feeding - less stress on the filtration system in the bigger tank, less stress on the fish in the bigger tank by not having to scoop out the dead ones.
Snipe I sold regular shiners and NOT Fathead minnows. We used to sell some called trotline shiners that were a lot larger but can't remember how many to a pound. Also this was probably 30 years ago!!
The tank has salt added but not the transport tub. The bullheads eat the dead minnows at the bottom. I remove as many dead minnows every day. So it has been a week and today 15 dead flatheads.
You have a good point. I buy from two suppliers. One get minnows and they do well. In fact some I bought a month ago are still doing very well. The other buyer I buy flatheads and they do die. I would say the flathead seller does not have the greatest set up.
I think I am going to try the holding tank suggestions. I do know when I picked the FHM up when I dumped from the bucket into the transport tub there were allot of dead ones already.
when I dumped from the bucket into the transport tub there were allot of dead ones already.
Okay this is a very good sign the FHM were in very bad, dying condition when you bought them. Get a different supplier.